Benzethonium chloride method for proteins adapted to centrifugal analysis.

A benzethonium chloride method for measuring protein concentrations in several types of body fluids has been adapted to the Cobas Bio centrifugal analyzer. The ability of this analyzer to add two reagents stepwise, measuring absorbances after each addition, is essential for proper blanking of urine specimens. The method has excellent curve stability and precision and yields results that correlate well with those of four other protein methods.